INSTALLATION AND SETUP 2-67
MON2000
JULY 2010 Hardware Setup
4. Connect a custom-made serial line cable (for
RS-232 serial transmission) from the serial
port of the external modem to an available
serial port on the GC Controller Terminal
Board for field wiring.
• Make note of the serial port number you
choose for connection. You will need this
information later to make appropriate
software settings.
• Use an RS-232 serial cable no longer
than 50 feet. Longer distances may
result in spurious loss or corruption of
transmitted data.
•See Section 5.17, for details of GC
Controller serial port connectivity (i.e.,
port locations, pinouts, connector types,
gender, cabling, etc.).
5. Connect a telephone line (from wall phone
jack, if available) to the phone jack for the
external modem.
6. Set external modem for Auto Answer (see
external modem user manual).
Special hardware modifications may be needed when
operating an external GC modem from the GC serial ports 3 or
4 (COM3 or COM4), as follows:
• DE-20782 (see drawing addendum of Model 500 Gas
Chromatograph System Hardware Reference Manual,
P/N 3-9000-537).
• Transient protection modules M7 and/or M4, located on the
back side of the GC Controller Terminal Board for field
wiring, may need replacement with the transient protection
modules for RS-232 signals (P/N 3-2350-027). Note that
M4 serves COM3 and M7 serves COM4.